Phosphinidynetrimethanol triacetate

ABSTRACT

1. A PROCESS FOR PREPARING PHOSPHINIDYNETRIMETHANOL TRIACETATE, WHICH PROCESS COMPRISES; (A) REACTING ACETIC ANHYDRIDE AND TETRAKIS(HYDROXYMETHYL)PHOSPHONIUM CHLORIDE IN PYRIDINE AT ROOM TEMPERATURE BY DISSOLVING 303 GRAMS (1.59 MOLES) OF SAID TETRAKIS(hYDROXYMETHYL)PHOOSPONIUM CHLORIDE IN 1800 MILLILITERS OF PYRIDINE AT ROOM TEMPERATURE, AND SLOWLY ADDING ABOUT 727 GRAMS (7.13 MOLES) OF ACETIC ANHYDRIDE WHILE STIRRING THE REACTION MIXTURE, TO MAINTAIN A TEMPERATURE OF THE MIXTURE AT BELOW 40*C; (B) CONTINUING THE REACTION UNTIL ALL OF THE TETRAKIS(HYDROXYMETHYL)PHOSPHONIUM CHLORIDE IS CONSUMED, THE SAID ACETIC ANHYDRIDE BEING PRESENT IN EXCESS; (C) REMOVING THE PYRIDINE BY DISTILLATION UNDER VACCUM TO OBTAIN AN OILY RESIDUE; (D) WASHING THE OILY DISTILLATION RESIDUE WITH WATER TO REMOVE UNREACTED STARTING MATERIALS AND UNDESIRED WATER-SOLUBLE PRODUCTS THEREBY OBTAINING A BROWN OIL WHICH SEPARATES; (D) DRYING THE SEPRATED BROWN OIL WITH ANHYDROUS SODIUM SULFATE OR SUITABLE SUBSTITUTE DRYING AGENT THEREFOR; AND (F) DISTILLING THE PRODUCT FROM (E) UNDER VACUUM TO OBTAIN PHOSPHINIDYNETRIMETHANOL TRIACETATE, A COLORLESS PRODUCT.

United States Patent Q 3,845,107 PHOSPHINIDYNETRIMETHANOL TRIACETATE Sigred B. Lanoux, Lafayette, Samuel E. Ellzey, Jr., New Orleans, and George L. Drake, Jr., and Wilson A. Reeves, Metaire, La., assignors to the United States of America as represented by the Secretary of Agriculture No Drawing. Original application Aug. 21, 1970, Ser. No. 66,084, new Patent No. 3,725,001. Divided and this application Mar. 2, 1972, Ser. No. 231,360

Int. Cl. C07c 67/00 US. Cl. 260488 J 1 Claim ABSTRACT OF THE DISCLOSURE Phosphinidynetrimethanol triacetate was prepared by reacting tetrakis(hydroxymethy1)phosphonium chloride with acetic anhydride in pyridine at room temperature. Cotton and other cellulosic textiles were treated with the product produced by the new process and found flame retardant.

A non-exclusive, irrevocable, royalty-free license in the invention herein described throughout the world for all purposes of the United States Government, with the power to grant sublicenses for such purposes, is hereby granted to the Government of the United States of America.

This invention relates to phosphinidynetrimethanol triacetate, to the preparation thereof, and to a process for imparting improved physical and chemical properties to cellulosic textiles by the treating of said cellulosic textiles with the organophosphorous compound of this invention. More specifically this invention relates to the preparation of a known compound by a new method, and to the utilization of this compound in textile applications which would yield goods with fire retardance and other useful properties.

The main objective of the instant is to provide a new method of preparing phosphinidynetrimethanol triacetate.

This is a division, of application Ser. No. 66,084, filed Aug. 21, 1970, now US. Pat. No. 3,725,001.

A second object of the instant invention is to provide a process for imparting to cotton and other cellulosic textiles improved fire retardance.

Phosphinidynetrimethanol triacetate was previously prepared by a reaction between tetrakis(hydroxymethyl) phosphonium chloride (THPC) and acetic anhydride in glacial acetic acid at 70-80" C. under a purified nitrogen atmosphere using concentrated H 80 as a catalyst to form tetrakis (acetoxymethyl)phosphonium chloride. This compound was neutralized with an aqueous solution of NaOH to form phosphinidynetrimethanol triacetate, (Zhur. Obshch. Khirn. 37, 2747). Addition of an aqueous solution of NaOH is a sensitive step in that the compound is easily oxidized to phosphinylidynetrimethanol triacetate.

According to the method of the instant invention phosphinidynetrimethanol triacetate is prepared directly in a one-step reaction and the sensitive step which involves the use of NaOH is avoided.

In the course of our investigations we have found that phosphinidynetrimethanol triacetate can be prepared by reacting THPC with acetic anhydride in pyridine at room temperautre. The reaction of THPC with acetic anhydride is carried out by slowly adding acetic anhydride to a pyridine solution of THPC.

'It was noted that phosphinidynetrimethanol triacetate became oxidized during storage in the presence of air to phosphinylidynetrimethanol triacetate to the extent of 30% in ten days.

The reaction with cellulosic material takes place in an undefined manner when a weight percent solution 3,845,107 Patented Oct. 29, 1974 ICC of phosphinidynetrimethanol triacetate in dimethylformamide is padded on the cellulosic material and the material is dried in an oven at C. for 5 minutes.

Cotton fibers, regenerated cotton fibers, paper, or other cellulosic materials are suitable for this invention. Cotton fiber is the preferred material, and may be in the form of fibers, sliver, yarn or fabric, but yarn or fabric is preferred.

The following examples illustrate procedures that have been used successfully in carrying out the invention. Cotton fabrics which have been treated by process of this invention were tested by standard methods recommended by the American Association of Textile Chemists and Colorists. Fabric combustibility tests were conducted according to AATCC test method 34-1966.

EXAMPLE 1 Preparation of Phosphinidynetrimethanol Triacetate Tetrakis(hydroxymethyl)phosphoniumchloride (303 g., 1.59 moles) was dissolved in 1800 ml. of pyridine. Acetic anhydride (727 g., 7.13 moles) was slowly added while the reaction mixture was stirred. No external source of heat was used and the reaction mixture never exceeded 40 C. The reaction mixture was stirred overnight. Volatile components of the reaction mixture were removed by distillation under vacuum. The oily residue was washed with water to remove starting materials and undesired water-soluble products. The brown oil which separated was dried with anhydrous sodium sulfate and distilled under vacuum to give g. of colorless product for a 39% yield. The boiling point of 138 C. at 0.275 mm. was recorded. Analytical: C H O P calculated C, 43.18; H, 6.06; P, 12.39. Found: C, 43.06; H, 6.16; P, 12.02.

A proton N.M.R. spectrum taken using a Varian A60A spectrometer confirmed that the product dissolved in acetone-d was pure by exhibiting only peaks realted to the compound, a methyl singlet at 124 cps. and a methylene doublet at 276.5 cps. (1:5 cps.). No other peaks were observed.

The compound is soluble in acetone, pyridine and dimethylformamide.

EXAMPLE 2 Demonstration of fire resistance of cotton fabric treated with phosphinidynetrimethanol triacetate A piece of cotton fabric approximately 12 inches by 12 inches (9.9 g.) was padded with an acetone (other solvents can be used) solution containing 15 weight percent phosphinidynetrimethanol triacetate and dried in an oven at 85 C. for five minutes. The treated fabric Weighed 13.1 g. The partially crosslinked fabric was tested for flame retardance according to AATCC test method 34-1966. There was no aftergolw and the fabric stopped burning before the gas burner was extinguished. The average char length was 4-5 inches.

EXAMPLE 3 Demonstration of fire resistance of paper treated with phosphinidynetrimethanol triacetate A piece of white 25% rag bond paper was treated with phosphinidynetrimethanol triacetate. Its flame retardancy properties were tested by holding a lighted match to the edge of the treated paper held horizontally. The paper burned to produce a hard black ash when the match flame was kept in contact with the edge of the paper. When the match flame was removed the flame of the paper extinguished itself.

3 4 We claim: sired water-soluble products thereby obtaining a 1. A process for preparing phosphinidynetrimethanol brown oil which separates; triacetate, which process comprises: (e) drying the separated brown oil with anhydrous (a) reacting acetic anhydride and tetrakis(hydroxysodium sulfate or siutable substitute drying agent methyl)phosphonium chloride in pyridine at room 5 therefor; and temperature by dissolving 303 grams (1.59 moles) (f) distilling the product from (e) under vacuum to of said tetrakis(hydroxymethyl)phosphonium chloobtain phosphinidynetrimethanol triacetate, a colorride in 1800 milliliters of pyridine at room temperaless product. ture, and slowly adding about 727 grams (7.13 References Cited moles) of acetic anhydride while stirring the re- 10 UNITED STATES PATENTS f i i gfggg j ?22 temperature the 3,214,434 10/1965 Grayson et a]. 260-488 F (b) continuing the reaction until all of the tetrakis(hy- OTHER REFERENCES V droxymethyl)phosphonium chloride is consumed, the Wagner Zook, Syn, Org, Chem., 482, 1953. I 7 said acetic anhydride being present in excess; 15

(c) removing the pyridine by distillatioin under vacuum VIVIAN GARNER, P y Examiner to obtain an oily residue; ((1) washing the oily distillation residue with water to remove unreactcd starting materials and unde- U7136 

1. A PROCESS FOR PREPARING PHOSPHINIDYNETRIMETHANOL TRIACETATE, WHICH PROCESS COMPRISES; (A) REACTING ACETIC ANHYDRIDE AND TETRAKIS(HYDROXYMETHYL)PHOSPHONIUM CHLORIDE IN PYRIDINE AT ROOM TEMPERATURE BY DISSOLVING 303 GRAMS (1.59 MOLES) OF SAID TETRAKIS(hYDROXYMETHYL)PHOOSPONIUM CHLORIDE IN 1800 MILLILITERS OF PYRIDINE AT ROOM TEMPERATURE, AND SLOWLY ADDING ABOUT 727 GRAMS (7.13 MOLES) OF ACETIC ANHYDRIDE WHILE STIRRING THE REACTION MIXTURE, TO MAINTAIN A TEMPERATURE OF THE MIXTURE AT BELOW 40*C; (B) CONTINUING THE REACTION UNTIL ALL OF THE TETRAKIS(HYDROXYMETHYL)PHOSPHONIUM CHLORIDE IS CONSUMED, THE SAID ACETIC ANHYDRIDE BEING PRESENT IN EXCESS; (C) REMOVING THE PYRIDINE BY DISTILLATION UNDER VACCUM TO OBTAIN AN OILY RESIDUE; (D) WASHING THE OILY DISTILLATION RESIDUE WITH WATER TO REMOVE UNREACTED STARTING MATERIALS AND UNDESIRED WATER-SOLUBLE PRODUCTS THEREBY OBTAINING A BROWN OIL WHICH SEPARATES; (D) DRYING THE SEPRATED BROWN OIL WITH ANHYDROUS SODIUM SULFATE OR SUITABLE SUBSTITUTE DRYING AGENT THEREFOR; AND (F) DISTILLING THE PRODUCT FROM (E) UNDER VACUUM TO OBTAIN PHOSPHINIDYNETRIMETHANOL TRIACETATE, A COLORLESS PRODUCT. 